IRIS Movie of the Day
At least once a week a movie of the Sun taken by NASA's Interface Region Imaging Spectrograph (IRIS) is posted by one of the scientists operating the instrument.
An Explosive Flare off of the Southeast Limb
Credit: IRIS, LMSAL/NASA, Chad Madsen
This video depicts one of the most energetic impulsive events in the solar system, the solar flare. These events occur when the magnetic field of the Sun becomes too structurally complex to sustain, resulting in a sudden reorganization of the field that releases immense amounts of energy. This observation shows a magnetically active region that has just rotated onto the southeast limb of the Sun. It will act as a stage for a flare that performs its spectacle in five acts. In Act I, we see warm material magnetically suspended above the limb in a tangled knot of thin arches, indicating a complicated magnetic structure in the area. In Act II, a sudden surge of bright material becomes apparent in the upper portion of limb, resulting in some of the suspended material draining back to the surface and suggesting that the magnetic field in the active region is beginning to consolidate. The climax happens in Act III where we see an immense brightening in the lower part of the limb accompanied by a huge rope of material forced outward into interplanetary space. In Act IV, we see the aftermath of the explosion as a bright flare ribbon zippers along the surface, covered by a long yet transient arcade of reconfigured magnetic field loops. Finally, in Act V, the active region relaxes into its newfound quiescent state.